introduction of cao

1. 4 th SEM(CSE) COMPUTER ARCHITECTURE AND ORGANIZATION - M. MORRIS MANO - J.P. Hayes

2. UNIT-I General System Architecture

4. Central Processing unit Program Control Arithmetic Logic Unit MAIN MEMORY Input –Output equipment Instructions data MAIN COMPONENTS OF MACHINE COMPUTATIONS

9. COMPUTER ORGANIZAION :- Is concerned with the way the hardware components operate and the way they are connected together to form the computer system. Components assumed to be in place and task is to investigate the organizational structure to verify that the computer parts operate as intended.

10. COMPUTER ARCHITECTURE :- Is concerned with the structure and the behavior of the computer as seen by the user. It includes the information formats, instruction set (IO, Data transfer), and techniques for addressing memory. The architectural design of a computer system is concerned with the specifications of the various functional modules such as processors and memories, and structuring them together into a computer system.

16. Instruction decoder …… . Control signals Program control unit (PCU) AR IR IBR PC DR Arithmetic- Logic unit AC MQ Data Processing unit DPU Address 0 1 2 3 4 4094 4095 M(2) M(1) M(0) M(3) M(4) M(4,094) M(4,095) Organization of CPU and main memory of IAS computer

22. FLYNN’S CLASSIFICATION OF COMPUTERS A processor as CPU operates by fetching instructions and operands from memory executing the instructions and placing the final result in memory. The instructions from an instruction stream flowing from memory to processor while the operands from another stream data stream, flowing to and from the processor. The sequence of instructions read from memory constitutes an instruction stream. The operations performed on the data in the processor constitutes a data stream. Memory M Processor P Instruction Stream Stream Data

23. Flynn has proposed a broad classification based on the number of simultaneous instruction streams and data streams seen by the processor during program execution . SISD (Single Instruction Stream, Single data stream) SIMD (Single Instruction Stream, Multiple data stream) MISD (Multiple Instruction Stream, Single data stream) MIMD (Multiple Instruction Stream, Multiple data stream) SISD represents the organization of a single computer containing a CU, a processor unit & a memory unit. SIMD represents an organization that includes many processing units under the supervision of a common control unit. MIMD refers to a computer system capable of processing several programs at the same time.

50. Central Processing Unit Addressing modes Numerical Example (M.M. 265) : Two word instruction at 200&201 Address=500 Next Instruction 450 700 800 900 325 300 Load to AC Mode Memory 500 Address 201 202 399 400 702 600 200 800 PC=200 R1=400 XR=100 AC Addressing mode eff. Add Content of AC ----------------------------------------------------------- Direct Address 500 800 Immediate operand 201 500 Indirect Address 800 300 Relative Address 702 (PC=PC+2) 325 Indexed Address 600 (XR+500) 900 Register --- 400 Register Indirect 400 700 Auto-increment 400 700 Auto-decrement 399 450 Tabular list